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11.
一氧化碳中毒迟发性脑病的临床预防 总被引:5,自引:0,他引:5
目的 探讨临床治疗措施对一氧化碳中毒迟发性脑病的预防。方法 将 130例一氧化碳中毒患者随机分为A、B、C 3组 ,A组采用纳络酮、低分子肝素、高压氧治疗 ;B组采用胞二磷胆碱、醒脑注射液、高压氧治疗 ;C组采用胞二磷胆碱、醒脑注射液治疗。结果 A组昏迷时间与B、C组对比 ,B组与C组对比 ,明显缩短 ,有显著性差异 (P <0 .0 5或P <0 .0 1) ;本组 130例患者中 ,共发生迟发性脑病15例 ,发生率为 11.5 % ,迟发性脑病发生率A组与B、C组对比 ,B组与C组对比 ,明显降低 ,有显著性差异 (P <0 .0 5或P <0 .0 1)。结论 选择有效的药物 ,及早应用高压氧和充足的疗程是迟发性脑病临床预防的关键。 相似文献
12.
The structure-acute toxicity relationship of aromatic hydrocarbons was examined in mice. In all test compounds, the acute toxicity was determined under 2 conditions: control LD50 (LD50-cont) and carbon tetrachloride (CCl4)-pretreated LD50 (LD50-CCl4). The CCl4-pretreatment was done in order to evaluate the toxic potency of compound itself without the influence of metabolism. Both log (1/LD50-cont) and log (1/LD50-CCl4) were functions of the log P, n-octanol/water partition coefficient, i.e., log (1/LD50-cont) = 0.080 log P − 1.532 and log (1/LD50-CCl4) = −0.040(log P)2 + 0.157 log P − 1.373. Both equations were statistically significant (P < 0.01). The ratio of LD50-cont/LD50-CCl4 indicated that metabolic activation is more evident in hydrophobic compounds than in hydrophilic compounds. The results suggest that hydrophobicity of the aromatic hydrocarbons plays an important role in determining their acute toxicity. 相似文献
13.
P. B. Dimakakos M. Papasavval T. Stefanopoulos D. Mourikis G. Kostopanagiotou A. Doufas 《European journal of plastic surgery》1997,20(3):132-135
Fourteen pigs with an average weight of 17 kg were used in this study. Under general anesthesia and magnification 1–3 ccm/kg of carbon dioxide were administered in the lymph vessels of the front and rear legs. Imaging of the peripheral lymph vessels, lymph nodes and the thoracic duct was achieved with digital subtraction angiography. The quality of lymphangiography was satisfactory and comparable with that of the standard non-ionic contrast agent. It is anticipated that further technical evolution will permit the application of CO2/DSA lymphangiography to man. Carbon dioxide is non-nephrotoxic and is non-allergic; it is inexpensive, can be administered in unlimited quantity and is quickly eliminated via the pulmonary system. 相似文献
14.
MRI of the brain in chronic carbon monoxide poisoning 总被引:3,自引:0,他引:3
We examined 13 patients with chronic carbon monoxide (CO) poisoning by magnetic resonance imaging (MRI); all of them had been in an explosion in a coal mine 25 years previously. Symmetrical globus pallidus lesions were observed in 12, as was degeneration of the white matter, with focal cortical atrophy. The temporal parietal and occipital lobes were usually affected, the parietooccipital region being the most frequently and extensively damaged. Of the 12 patients with white matter degeneration 7 had definitely asymmetrical cortical and subcortical lesions. There were 6 patients with dilated temporal horns, probably due to atrophy of the hippocampal gyri. A history of CO inhalation and an awareness of the typical distributions of lesions are important for recognition of the effects of CO poisoning, especially when patients are in the chronic stage. 相似文献
15.
M. Guillemin H. Cachier C. Chini D. Dabill D. Dahmann F. Diebold A. Fischer H.-H. Fricke J. A. Groves R. Hebisch M. Houpillart G. Israël M. Mattenklott W. Moldenhauer J. P. Sandino C. Schlums E. Sutter E. Tucek 《International archives of occupational and environmental health》1997,70(3):161-172
Object: Diesel soot has been recognized as probably carcinogenic to humans. Elemental carbon (also called black carbon) in soot
is considered at the moment as the most significant surrogate to be measured for assessing the exposure to this pollutant.
Its analysis is done by combustion in an oven and determination of the CO2 formed, after elimination of the organic fraction of the soot by heating and/or by solvent extraction. The analysis allows
determination of both fractions of the soot: “elemental carbon” (EC) and organic carbon␣(OC). The sum of EC and OC is called
TC (total carbon). Method: An informal European coordination group organized two round robin tests on filter samples collected from diluted diesel
emissions. The first round (RRT1) was performed on 13 different samples analyzed by ten laboratories. The range of loading
was 2.5 to 150 μg/cm2 of EC. No evaluation of the precision within laboratories could be made since each laboratory gave only one result per sample.
Therefore a second round (RRT2) was organized with two samples and a blank filter sent in several portions to 11 laboratories.
It should be stressed that each laboratory used its own method and that no standardization was planned at this stage. Results: Results of RRT1 showed that the coefficient of variation between laboratories decreased with higher loading and was around
10% to 15% for EC above about 20 μg/cm2. Dispersion of the results varied and it appeared that the way OC is removed from the soot is probably the most important
factor of influence. The correlation between the laboratories was good as a whole but some systematic differences could be
detected. Besides the different techniques to remove the organic carbon, the pretreatment of the filter by HCl (either as
a vapor or as a solution) to remove the inorganic carbonates (potential interference sources), is probably also a significant
factor of influence in the dispersion of the results between laboratories. It is not yet clear from these results whether
the “environmental” laboratories give different results from the “occupational” laboratories, but it is clear that their objectives
differ since for the “environmentalists”, EC is not a specific marker of diesel immissions, in contrast to the “occupationalists”.
Conclusion: It can be concluded that, although significant differences exist between laboratories they can be attributed mainly to the
narrow distribution of the results within a single laboratory, and that the overall agreement of the results for EC and TC
is fairly good. These results obtained with pure diesel engine emissions, should be complemented by field samples, but they
have already achieved relevant findings in the performance of the procedures used to assess exposure to diesel soot.
Received: 30 December 1996 / Accepted: 21 February 1997 相似文献
16.
Andrea Veltri Simona Capello Barbara Faissola Francesco Spalluto Sergio Farinet Maurizio Grosso 《Cardiovascular and interventional radiology》1994,17(3):133-137
Purpose The goal of the study is to evaluate utility of contrast enhanced ultrasound (US) with carbon dioxide microbubbles in evaluation of hepatic lesions.Methods Twenty eight patients with single or multiple t hepatic lesions (11 hepatocellular carcinoma, 8 hemangiomas, 5 metastases, 1 adenoma, 1 focal nodular hyperplasia, 2 regenerative nodules) were examined. US exam was performed during intraarterial injection of 10 ml of CO2 through the same catheter employed for liver arteriography. The US exam was videotaped in its salient phases. Characteristics of enhancement were evaluated and correlated with histological findings or patient follow up.Results Sonographic angiography clearly demonstrated vascularization of the lesions. Hepatocellular carcinoma, hemangioma, metastases, focal nodular hyperplasia, and regenerative nodules had very characteristic patterns. The injection of CO2 allowed detection of small additional nodules.Conclusion Sonographic angiography can improve characterization and staging of hepatic tumors. Low cost and the simplicity of the technique should encourage further experimentation. 相似文献
17.
目的对二氧化碳吸入、屏气及过度换气等3种不同的脑血管反应性检测方法进行比较,拟为临床应用探索一种有效且简便的方法。方法70例健康体格检查者通过经颅多普勒(TCD)超声技术常规检测颅底及颈部各动脉,然后分别进行二氧化碳吸入试验、过度换气试验和屏气试验,记录试验前后双侧大脑中动脉血流速度变化数据和趋势,检测脑血管反应性。结果吸入二氧化碳后,大脑中动脉平均血流速度明显加快,增加率为(44.86±10.18)%;过度换气时,平均血流速度明显减慢,于过度换气20~30s后降至平台期,平均下降率为(33.63±8.62)%,直至过度通气结束血流速度无明显变化。70例受试者平均屏气时间为(41.66±9.51)s,其中男性屏气时间(42.05±9.23)s,女性(40.63±10.47)s,男女之间差异无统计学意义(P>0.05);屏气后大脑中动脉平均血流速度明显加快,增加率为(46.53±11.83)%;平均屏气指数为1.16±0.37;屏气后血流速度增加率和屏气指数之间呈高度正相关(r=0.865,P<0.01);当屏气时间>30s时,无论采用屏气后血流速度增加率或屏气指数作为分析指标,均可准确地反映脑血管反应性变化。对二氧化碳吸入试验、过度换气试验及屏气试验3种不同方法进行比较显示,过度换气试验与二氧化碳吸入试验、屏气试验间差异有统计学意义(P<0.01);而二氧化碳吸入试验与屏气试验之间差异无统计学意义(P>0.05)。结论二氧化碳吸入试验、屏气试验和过度换气试验均可有效地评价脑血管反应性,其中以屏气试验评价脑血管反应性更为简便。 相似文献
18.
Ricardo GONZALEZ Odelsa ANCHETA Marlien MARQUEZ Sandra RODRIGUEZ 《Acta pharmacologica Sinica》1994,(6)
This research was carried out to determine a potential role of leukotrienes in the acute hepatotoxicity induced by CC14 in rats. An inhibitor of leukotrienes biosynthesis, diethylcarbamazine (DEC, 25 and 50 mg ·kg-1 ip) exerted hepatoprotective effects, decreasing the activity of alanine aminotransfer-ase in serum and the concentration of liver triglycerides. DEC reduced histological damage of liver evidenced by electron microscopy. The hepatoprotective effects of DEC were dose-dependent. The results favor the role of leukotrienes in CC14 hepatotoxicity. 相似文献
19.
Masahiko Kawaguchi Masakazu Kuro Hisatoshi Ohsumi Toshito Nakajima Yoshihiro Kuriyama Jun Karasawa 《Journal of anesthesia》1994,8(1):60-63
We assessed the local cerebral blood flow (LCBF) in 40 patients under fentanyl-diazepam anesthesia. The measurement of LCBF
was made using 50%–70% stable xenon with 20 min of inhalation interval and a shuttle method for computed tomography imaging.
All patients were anesthetized with 5.95±1.76 μg·kg−1 fentanyl and 0.22±0.07 mg·kg−1 diazepam under mechanical ventilation during CBF measurement. The values and distribution of LCBF on non-affected hemisphere
appeared to be unaltered by fentanyldiazepam anesthesia. We also assessed the cerebral carbon dioxide reactivity in 6 patients.
The cerebral carbon dioxide reactivity, expressed as percentage change in LCBF per unit change in arterial carbon dioxide
partial pressure, was 5.39±1.07, and there were no significant differences of reactivity among regions studied. In conclusion,
we showed reference values of LCBF and carbon dioxide reactivity, measured by stable xenon-enhanced computed tomography, in
patients under fentanyl-diazepam anesthesia. Carbon dioxide reactivity was preserved in all regions including gray matter,
white matter, and basal ganglia. 相似文献
20.
Toshiaki Nakashima Fuminori Goda Jinge Jiang Toshihide Shima Harold M. Swartz 《Magnetic resonance in medicine》1995,34(6):888-892
The partial pressure of oxygen (pO2) of the liver in vivo in unanesthetized mice was determined using electron paramagnetic resonance (EPR) oximetry with India ink. The EPR spectra were obtained using a low-frequency (1.2 GHz) EPR spectrometer with a loop gap cavity resonator. The line width of the India ink used in this experiment was reversibly broadened by oxygen and was particularly sensitive to pO2 below 30 torr. After the administration of India ink into the tail vein, the India ink particles were taken up mainly by Kupffer cells in the liver and in part by phagocytes in the spleen. The pO2 measured in the normal liver was about 14 torr and was constant for the 2-week experimental period. The pO2 decreased when measured at 1, 2, and 6 days after treatment with a hepatotoxin (carbon tetrachloride (CCI4)); within 2 weeks, it returned almost to the initial level. Measurements by EPR at sacrifice of controls and CCI4-treated mice indicated that more than 90% of the India ink went to the liver; the spleen contained 4.7% of total amount in control mice and 8.8% in CCI4-treated mice when measured 2 weeks after the treatment. These data indicate the usefulness of India ink for measuring the pO2 of the liver in vivo and that the pO2 in the Kupffer cells is decreased when the liver is damaged by CCI4. 相似文献